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96
result(s) for
"Han, Mei Lan K."
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Relationship between diffusion capacity and small airway abnormality in COPDGene
by
Curtis, Jeffrey L.
,
Martinez, Fernando J.
,
Labaki, Wassim W.
in
Aged
,
Airway management
,
Airway Obstruction - diagnostic imaging
2019
Impaired single breath carbon monoxide diffusing capacity (DLCO) is associated with emphysema. Small airways disease (SAD) may be a precursor lesion to emphysema, but the relationship between SAD and DLCO is undescribed. We hypothesized that in mild COPD, functional SAD (fSAD) defined by computed tomography (CT) and Parametric Response Mapping methodology would correlate with impaired DLCO. Using data from ever-smokers in the COPDGene cohort, we established that fSAD correlated significantly with lower DLCO among both non-obstructed and GOLD 1–2 subjects. The relationship between DLCO with CT-defined emphysema was present in all GOLD stages, but most prominent in severe disease.
Trial registration
NCT00608764
. Registry: COPDGene. Registered 06 February 2008, retrospectively registered.
Journal Article
Genome-wide association study of lung function and clinical implication in heavy smokers
by
Dransfield, Mark T.
,
Cooper, Christopher B.
,
Meyers, Deborah A.
in
Aged
,
alpha 1-Antitrypsin - genetics
,
Biomedical and Life Sciences
2018
Background
The aim of this study is to identify genetic loci associated with post-bronchodilator FEV
1
/FVC and FEV
1
, and develop a multi-gene predictive model for lung function in COPD.
Methods
Genome-wide association study (GWAS) of post-bronchodilator FEV
1
/FVC and FEV
1
was performed in 1645 non-Hispanic White European descent smokers.
Results
A functional rare variant in
SERPINA1
(rs28929474: Glu342Lys) was significantly associated with post-bronchodilator FEV
1
/FVC (
p
= 1.2 × 10
− 8
) and FEV
1
(
p
= 2.1 × 10
− 9
). In addition, this variant was associated with COPD (OR = 2.3;
p
= 7.8 × 10
− 4
) and severity (OR = 4.1;
p
= 0.0036). Heterozygous subjects (CT genotype) had significantly lower lung function and higher percentage of COPD and more severe COPD than subjects with the CC genotype. 8.6% of the variance of post-bronchodilator FEV
1
/FVC can be explained by SNPs in 10 genes with age, sex, and pack-years of cigarette smoking (
P
< 2.2 × 10
− 16
).
Conclusions
This study is the first to show genome-wide significant association of rs28929474 in
SERPINA1
with lung function. Of clinical importance, heterozygotes of rs28929474 (4.7% of subjects) have significantly reduced pulmonary function, demonstrating a major impact in smokers. The multi-gene model is significantly associated with CT-based emphysema and clinical outcome measures of severity. Combining genetic information with demographic and environmental factors will further increase the predictive power for assessing reduced lung function and COPD severity.
Journal Article
Once-Daily Single-Inhaler Triple versus Dual Therapy in Patients with COPD
by
Pascoe, Steven J
,
Criner, Gerard J
,
Martinez, Fernando J
in
Acetylcholine receptors (muscarinic)
,
Administration, Inhalation
,
Adrenergic beta-Agonists - administration & dosage
2018
The frequency of COPD exacerbations during treatment with a triple inhaler — delivering a long-acting beta-agonist (LABA), a long-acting muscarinic antagonist (LAMA), and an inhaled glucocorticoid — was compared with that with a LABA–LAMA or LABA–inhaled glucocorticoid.
Journal Article
Lung Microbiota Contribute to Pulmonary Inflammation and Disease Progression in Pulmonary Fibrosis
by
Norman, Katy C.
,
Falkowski, Nicole R.
,
O’Dwyer, David N.
in
Aged
,
Animals
,
Bronchoalveolar Lavage Fluid - microbiology
2019
Idiopathic pulmonary fibrosis (IPF) causes considerable global morbidity and mortality, and its mechanisms of disease progression are poorly understood. Recent observational studies have reported associations between lung dysbiosis, mortality, and altered host defense gene expression, supporting a role for lung microbiota in IPF. However, the causal significance of altered lung microbiota in disease progression is undetermined.
To examine the effect of microbiota on local alveolar inflammation and disease progression using both animal models and human subjects with IPF.
For human studies, we characterized lung microbiota in BAL fluid from 68 patients with IPF. For animal modeling, we used a murine model of pulmonary fibrosis in conventional and germ-free mice. Lung bacteria were characterized using 16S rRNA gene sequencing with novel techniques optimized for low-biomass sample load. Microbiota were correlated with alveolar inflammation, measures of pulmonary fibrosis, and disease progression.
Disruption of the lung microbiome predicts disease progression, correlates with local host inflammation, and participates in disease progression. In patients with IPF, lung bacterial burden predicts fibrosis progression, and microbiota diversity and composition correlate with increased alveolar profibrotic cytokines. In murine models of fibrosis, lung dysbiosis precedes peak lung injury and is persistent. In germ-free animals, the absence of a microbiome protects against mortality.
Our results demonstrate that lung microbiota contribute to the progression of IPF. We provide biological plausibility for the hypothesis that lung dysbiosis promotes alveolar inflammation and aberrant repair. Manipulation of lung microbiota may represent a novel target for the treatment of IPF.
Journal Article
Improving Detection of Early Chronic Obstructive Pulmonary Disease
by
Labaki, Wassim W.
,
Han, MeiLan K.
in
Airway management
,
Artificial intelligence
,
Chronic obstructive pulmonary disease
2018
Despite being a major cause of morbidity and mortality, chronic obstructive pulmonary disease (COPD) is frequently undiagnosed. Yet the burden of disease among the undiagnosed is significant, as these individuals experience symptoms, exacerbations, and excess mortality compared to those without COPD. The U.S. Preventive Services Task Force recommends against routine screening of asymptomatic individuals with spirometry. Hence, case-finding approaches are needed. A recently developed instrument, the five-item COPD Assessment in Primary Care to Identify Undiagnosed Respiratory Disease and Exacerbation Risk questionnaire plus peak expiratory flow, demonstrates good sensitivity and specificity for distinguishing cases from control subjects and is being studied prospectively in primary care settings to determine its impact on patient outcomes. However, finding the undiagnosed is only half the battle. Mounting evidence suggests significant COPD-like respiratory burden among individuals without airflow obstruction. Many experience dyspnea, mucus production, and exacerbation events and have emphysema and airway abnormalities on computed tomographic (CT) imaging of the chest. However, it is still unclear how to best treat these individuals and which individuals go on to develop spirometric obstruction. These challenges underline the importance of defining what constitutes \"early disease.\" A recently proposed definition characterizes early COPD as either: 1) airflow limitation, 2) compatible CT imaging abnormalities, or 3) accelerated forced expiratory volume in 1 second decline in persons younger than 50 years and with greater than a 10 pack-year smoking history. Although it is recognized that this definition does not encompass all individuals who will develop COPD, it is an attempt to identify a group of individuals with most rapid decline to better understand mechanisms of disease development and where disease-modifying interventions are most likely to be successful. Ultimately, leveraging tools such as chest CT imaging, the electronic medical record, and machine learning algorithms may aid in the identification of such individuals.
Journal Article
Airway Mucin Concentration as a Marker of Chronic Bronchitis
2017
Chronic bronchitis is currently diagnosed by asking patients if they expectorate sputum on a regular basis. In this study, the concentration of mucin was higher in the induced sputum of patients with chronic bronchitis than in those who did not meet the case definition of the disorder.
Journal Article
Bronchodilators in Tobacco-Exposed Persons with Symptoms and Preserved Lung Function
by
Criner, Gerard J.
,
Buhr, Russell G.
,
Drescher, Frank
in
Adrenergic beta-2 Receptor Agonists - therapeutic use
,
Anti-Bacterial Agents - therapeutic use
,
Antibiotics
2022
Many persons with a history of smoking tobacco have clinically significant respiratory symptoms despite an absence of airflow obstruction as assessed by spirometry. They are often treated with medications for chronic obstructive pulmonary disease (COPD), but supporting evidence for this treatment is lacking.
We randomly assigned persons who had a tobacco-smoking history of at least 10 pack-years, respiratory symptoms as defined by a COPD Assessment Test score of at least 10 (scores range from 0 to 40, with higher scores indicating worse symptoms), and preserved lung function on spirometry (ratio of forced expiratory volume in 1 second [FEV
] to forced vital capacity [FVC] ≥0.70 and FVC ≥70% of the predicted value after bronchodilator use) to receive either indacaterol (27.5 μg) plus glycopyrrolate (15.6 μg) or placebo twice daily for 12 weeks. The primary outcome was at least a 4-point decrease (i.e., improvement) in the St. George's Respiratory Questionnaire (SGRQ) score (scores range from 0 to 100, with higher scores indicating worse health status) after 12 weeks without treatment failure (defined as an increase in lower respiratory symptoms treated with a long-acting inhaled bronchodilator, glucocorticoid, or antibiotic agent).
A total of 535 participants underwent randomization. In the modified intention-to-treat population (471 participants), 128 of 227 participants (56.4%) in the treatment group and 144 of 244 (59.0%) in the placebo group had at least a 4-point decrease in the SGRQ score (difference, -2.6 percentage points; 95% confidence interval [CI], -11.6 to 6.3; adjusted odds ratio, 0.91; 95% CI, 0.60 to 1.37; P = 0.65). The mean change in the percent of predicted FEV
was 2.48 percentage points (95% CI, 1.49 to 3.47) in the treatment group and -0.09 percentage points (95% CI, -1.06 to 0.89) in the placebo group, and the mean change in the inspiratory capacity was 0.12 liters (95% CI, 0.07 to 0.18) in the treatment group and 0.02 liters (95% CI, -0.03 to 0.08) in the placebo group. Four serious adverse events occurred in the treatment group, and 11 occurred in the placebo group; none were deemed potentially related to the treatment or placebo.
Inhaled dual bronchodilator therapy did not decrease respiratory symptoms in symptomatic, tobacco-exposed persons with preserved lung function as assessed by spirometry. (Funded by the National Heart, Lung, and Blood Institute and others; RETHINC ClinicalTrials.gov number, NCT02867761.).
Journal Article
The prevalence and mortality risks of PRISm and COPD in the United States from NHANES 2007–2012
2024
Background
We estimated the prevalence and mortality risks of preserved ratio impaired spirometry (PRISm) and chronic obstructive pulmonary disease (COPD) in the US adult population.
Methods
We linked three waves of pre-bronchodilator spirometry data from the US National Health and Nutritional Examination Survey (2007–2012) with the National Death Index. The analytic sample included adults ages 20 to 79 without missing data on age, sex, height, BMI, race/ethnicity, and smoking status. We defined COPD (GOLD 1, 2, and 3–4) and PRISm using FEV
1
/FVC cut points by the Global Initiative for Chronic Obstructive Lung Disease (GOLD). We compared the prevalence of GOLD stages and PRISm by covariates across the three waves. We estimated adjusted all-cause and cause-specific mortality risks by COPD stage and PRISm using all three waves combined.
Results
Prevalence of COPD and PRISm from 2007–2012 ranged from 13.1%-14.3% and 9.6%-10.2%, respectively. We found significant differences in prevalence by sex, age, smoking status, and race/ethnicity. Males had higher rates of COPD regardless of stage, while females had higher rates of PRISm. COPD prevalence increased with age, but not PRISm, which was highest among middle-aged individuals. Compared to current and never smokers, former smokers showed lower rates of PRISm but higher rates of GOLD 1. COPD prevalence was highest among non-Hispanic White individuals, and PRISm was notably higher among non-Hispanic Black individuals (range 31.4%-37.4%). We found associations between PRISm and all-cause mortality (hazard ratio [HR]: 2.3 95% CI: 1.9—2.9) and various cause-specific deaths (HR ranges: 2.0–5.3). We also found associations between GOLD 2 (HR: 2.1, 95% CI: 1.7–2.6) or higher (HR: 4.2, 95% CI: 2.7–6.5) and all-cause mortality. Cause-specific mortality risk varied within COPD stages but typically increased with higher GOLD stage.
Conclusions
The prevalence of COPD and PRISm remained stable from 2007–2012. Greater attention should be paid to the potential impacts of PRISm due to its higher prevalence in minority groups and its associations with mortality across various causes including cancer.
Journal Article
Lymphangioleiomyomatosis Diagnosis and Management: High-Resolution Chest Computed Tomography, Transbronchial Lung Biopsy, and Pleural Disease Management. An Official American Thoracic Society/Japanese Respiratory Society Clinical Practice Guideline
by
Taveira-DaSilva, Angelo M.
,
Seyama, Kuniaki
,
Colby, Thomas V.
in
Adult
,
Aged
,
Aged, 80 and over
2017
Recommendations regarding key aspects related to the diagnosis and pharmacological treatment of lymphangioleiomyomatosis (LAM) were recently published. We now provide additional recommendations regarding four specific questions related to the diagnosis of LAM and management of pneumothoraces in patients with LAM.
Systematic reviews were performed and then discussed by a multidisciplinary panel. For each intervention, the panel considered its confidence in the estimated effects, the balance of desirable (i.e., benefits) and undesirable (i.e., harms and burdens) consequences, patient values and preferences, cost, and feasibility. Evidence-based recommendations were then formulated, written, and graded using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) approach.
For women who have cystic changes on high-resolution computed tomography of the chest characteristic of LAM, but who have no additional confirmatory features of LAM (i.e., clinical, radiologic, or serologic), the guideline panel made conditional recommendations against making a clinical diagnosis of LAM on the basis of the high-resolution computed tomography findings alone and for considering transbronchial lung biopsy as a diagnostic tool. The guideline panel also made conditional recommendations for offering pleurodesis after an initial pneumothorax rather than postponing the procedure until the first recurrence and against pleurodesis being used as a reason to exclude patients from lung transplantation.
Evidence-based recommendations for the diagnosis and treatment of patients with LAM are provided. Frequent reassessment and updating will be needed.
Journal Article
Noninvasive Imaging Biomarker Identifies Small Airway Damage in Severe Chronic Obstructive Pulmonary Disease
2019
Evidence suggests damage to small airways is a key pathologic lesion in chronic obstructive pulmonary disease (COPD). Computed tomography densitometry has been demonstrated to identify emphysema, but no such studies have been performed linking an imaging metric to small airway abnormality.
To correlate
parametric response mapping (PRM) analysis to
lung tissue measurements of patients with severe COPD treated by lung transplantation and control subjects.
Resected lungs were inflated, frozen, and systematically sampled, generating 33 COPD (
= 11 subjects) and 22 control tissue samples (
= 3 subjects) for micro-computed tomography analysis of terminal bronchioles (TBs; last generation of conducting airways) and emphysema.
PRM analysis was conducted to differentiate functional small airways disease (PRM
) from emphysema (PRM
). In COPD lungs, TB numbers were reduced (
= 0.01); surviving TBs had increased wall area percentage (
< 0.001), decreased circularity (
< 0.001), reduced cross-sectional luminal area (
< 0.001), and greater airway obstruction (
= 0.008). COPD lungs had increased airspace size (
< 0.001) and decreased alveolar surface area (
< 0.001). Regression analyses demonstrated unique correlations between PRM
and TBs, with decreased circularity (
< 0.001), decreased luminal area (
< 0.001), and complete obstruction (
= 0.008). PRM
correlated with increased airspace size (
< 0.001), decreased alveolar surface area (
= 0.003), and fewer alveolar attachments per TB (
= 0.01).
PRM
identifies areas of lung tissue with TB loss, luminal narrowing, and obstruction. This is the first confirmation that an imaging biomarker can identify terminal bronchial pathology in established COPD and provides a noninvasive imaging methodology to identify small airway damage in COPD.
Journal Article